Implement Ruff

[aedwardstx]

Please implement the Ruff linter and resolve issues. I suggest configuring Ruff with all rules enabled by default and then selectively disable problematic rules. Ruff covers a significant fraction of pylint's rules and those from many other linters. Ruff implements all or virtually all of flake8 rules - so, you could remove flake8. Ruff should be run under Github CI.